Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932770AbaFCLlr (ORCPT ); Tue, 3 Jun 2014 07:41:47 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:43592 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932746AbaFCLlp (ORCPT ); Tue, 3 Jun 2014 07:41:45 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Anthony Iliopoulos , "H. Peter Anvin" , Luis Henriques Subject: [PATCH 3.11 075/138] x86, mm, hugetlb: Add missing TLB page invalidation for hugetlb_cow() Date: Tue, 3 Jun 2014 12:38:41 +0100 Message-Id: <1401795584-22664-76-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1401795584-22664-1-git-send-email-luis.henriques@canonical.com> References: <1401795584-22664-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.11.10.11 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Anthony Iliopoulos commit 9844f5462392b53824e8b86726e7c33b5ecbb676 upstream. The invalidation is required in order to maintain proper semantics under CoW conditions. In scenarios where a process clones several threads, a thread operating on a core whose DTLB entry for a particular hugepage has not been invalidated, will be reading from the hugepage that belongs to the forked child process, even after hugetlb_cow(). The thread will not see the updated page as long as the stale DTLB entry remains cached, the thread attempts to write into the page, the child process exits, or the thread gets migrated to a different processor. Signed-off-by: Anthony Iliopoulos Link: http://lkml.kernel.org/r/20140514092948.GA17391@server-36.huawei.corp Suggested-by: Shay Goikhman Acked-by: Dave Hansen Signed-off-by: H. Peter Anvin Signed-off-by: Luis Henriques --- arch/x86/include/asm/hugetlb.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/include/asm/hugetlb.h b/arch/x86/include/asm/hugetlb.h index a8091216963b..68c05398bba9 100644 --- a/arch/x86/include/asm/hugetlb.h +++ b/arch/x86/include/asm/hugetlb.h @@ -52,6 +52,7 @@ static inline pte_t huge_ptep_get_and_clear(struct mm_struct *mm, static inline void huge_ptep_clear_flush(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) { + ptep_clear_flush(vma, addr, ptep); } static inline int huge_pte_none(pte_t pte) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/